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Reclassification from AOCI, Current Period [Abstract]

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount before tax and reclassification adjustments of other comprehensive income (loss) attributable to parent.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) before reclassification adjustment from accumulated other comprehensive income (loss).

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss).

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
BALANCE	$ 1,127,713	$ 1,178,079	$ 1,095,694	$ 1,124,282
Other comprehensive income (loss) before reclassifications
Pre-tax			(18,357)	(1,440)
Tax effect			4,253	(3,570)
Amounts reclassified from accumulated other comprehensive income (loss)
Tax effect			203	(593)
Net current period other comprehensive income (loss)	(13,781)	(20,408)	(14,758)	(3,132)
BALANCE	1,164,065	1,172,612	1,164,065	1,172,612
Floorplan interest expense (pre-tax)
Amounts reclassified from accumulated other comprehensive income (loss)
Pre-tax			(618)	2,999
Other interest expense, net (pre-tax)
Amounts reclassified from accumulated other comprehensive income (loss)
Pre-tax			(239)	390
Realized gain on swap termination (pre-tax)
Amounts reclassified from accumulated other comprehensive income (loss)
Pre-tax				(918)
Accumulated other comprehensive income (loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
BALANCE	(138,749)	(105,950)	(137,772)	(123,226)
Amounts reclassified from accumulated other comprehensive income (loss)
Net current period other comprehensive income (loss)	(13,781)	(20,408)	(14,758)	(3,132)
BALANCE	(152,530)	(126,358)	(152,530)	(126,358)
Accumulated income (loss) on foreign currency translation
Accumulated Other Comprehensive Income (Loss) [Line Items]
BALANCE			(146,708)	(122,552)
Other comprehensive income (loss) before reclassifications
Pre-tax			(413)	(16,315)
Tax effect			0	0
Amounts reclassified from accumulated other comprehensive income (loss)
Tax effect			0	0
Net current period other comprehensive income (loss)			(413)	(16,315)
BALANCE	(147,121)	(138,867)	(147,121)	(138,867)
Accumulated income (loss) on foreign currency translation \| Floorplan interest expense (pre-tax)
Amounts reclassified from accumulated other comprehensive income (loss)
Pre-tax			0	0
Accumulated income (loss) on foreign currency translation \| Other interest expense, net (pre-tax)
Amounts reclassified from accumulated other comprehensive income (loss)
Pre-tax			0	0
Accumulated income (loss) on foreign currency translation \| Realized gain on swap termination (pre-tax)
Amounts reclassified from accumulated other comprehensive income (loss)
Pre-tax				0
Accumulated income (loss) on interest rate swaps
Accumulated Other Comprehensive Income (Loss) [Line Items]
BALANCE			8,936	(674)
Other comprehensive income (loss) before reclassifications
Pre-tax			(17,944)	14,875
Tax effect			4,253	(3,570)
Amounts reclassified from accumulated other comprehensive income (loss)
Tax effect			203	(593)
Net current period other comprehensive income (loss)			(14,345)	13,183
BALANCE	$ (5,409)	$ 12,509	(5,409)	12,509
Accumulated income (loss) on interest rate swaps \| Floorplan interest expense (pre-tax)
Amounts reclassified from accumulated other comprehensive income (loss)
Pre-tax			(618)	2,999
Accumulated income (loss) on interest rate swaps \| Other interest expense, net (pre-tax)
Amounts reclassified from accumulated other comprehensive income (loss)
Pre-tax			$ (239)	390
Accumulated income (loss) on interest rate swaps \| Realized gain on swap termination (pre-tax)
Amounts reclassified from accumulated other comprehensive income (loss)
Pre-tax				$ (918)